On a scaled drawing, the ratio 1:100 defines the relationship between the length on the drawing and the length in real life. For example, a length of 1 centimeter on the drawing means that the length of the object in real life is 100 centimeters.
According to the Engineering Toolbox, one common application of a scaled drawing on a 1:100 scale is a building plan. Each meter in the drawing refers to a length of 100 actual meters in the building's physical layout. Larger scales, such as 1:1000, are used for block or city planning, and scales like 1:10000 and 1:100000 are used for ordinance survey maps. Smaller scales, such as 1:5 or 1:40, may be used for detailed component drawings or floor planning.